Slightly reduce RAM usage (#7301)

* No need to re-require sidekiq plugins, they are required via Gemfile

* Add derailed_benchmarks tool, no need to require TTY gems in Gemfile

* Replace ruby-oembed with FetchOEmbedService

Reduce startup by 45382 allocated objects

* Remove preloaded JSON-LD in favour of caching HTTP responses

Reduce boot RAM by about 6 MiB

* Fix tests

* Fix test suite by stubbing out JSON-LD contexts

3 files changed, 552 insertions, 0 deletions

diff --git a/spec/fixtures/requests/json-ld.activitystreams.txt b/spec/fixtures/requests/json-ld.activitystreams.txt
new file mode 100644
index 000000000..395797b27
--- /dev/null
+++ b/spec/fixtures/requests/json-ld.activitystreams.txt
@@ -0,0 +1,391 @@
+HTTP/1.1 200 OK

+Date: Tue, 01 May 2018 23:25:57 GMT

+Content-Location: activitystreams.jsonld

+Vary: negotiate,accept

+TCN: choice

+Last-Modified: Mon, 16 Apr 2018 00:28:23 GMT

+ETag: "1eb0-569ec4caa97c0;d3-540ee27e0eec0"

+Accept-Ranges: bytes

+Content-Length: 7856

+Cache-Control: max-age=21600

+Expires: Wed, 02 May 2018 05:25:57 GMT

+P3P: policyref="http://www.w3.org/2014/08/p3p.xml"

+Access-Control-Allow-Origin: *

+Content-Type: application/ld+json

+Strict-Transport-Security: max-age=15552000; includeSubdomains; preload

+Content-Security-Policy: upgrade-insecure-requests

+

+{
+  "@context": {
+    "@vocab": "_:",
+    "xsd": "http://www.w3.org/2001/XMLSchema#",
+    "as": "https://www.w3.org/ns/activitystreams#",
+    "ldp": "http://www.w3.org/ns/ldp#",
+    "id": "@id",
+    "type": "@type",
+    "Accept": "as:Accept",
+    "Activity": "as:Activity",
+    "IntransitiveActivity": "as:IntransitiveActivity",
+    "Add": "as:Add",
+    "Announce": "as:Announce",
+    "Application": "as:Application",
+    "Arrive": "as:Arrive",
+    "Article": "as:Article",
+    "Audio": "as:Audio",
+    "Block": "as:Block",
+    "Collection": "as:Collection",
+    "CollectionPage": "as:CollectionPage",
+    "Relationship": "as:Relationship",
+    "Create": "as:Create",
+    "Delete": "as:Delete",
+    "Dislike": "as:Dislike",
+    "Document": "as:Document",
+    "Event": "as:Event",
+    "Follow": "as:Follow",
+    "Flag": "as:Flag",
+    "Group": "as:Group",
+    "Ignore": "as:Ignore",
+    "Image": "as:Image",
+    "Invite": "as:Invite",
+    "Join": "as:Join",
+    "Leave": "as:Leave",
+    "Like": "as:Like",
+    "Link": "as:Link",
+    "Mention": "as:Mention",
+    "Note": "as:Note",
+    "Object": "as:Object",
+    "Offer": "as:Offer",
+    "OrderedCollection": "as:OrderedCollection",
+    "OrderedCollectionPage": "as:OrderedCollectionPage",
+    "Organization": "as:Organization",
+    "Page": "as:Page",
+    "Person": "as:Person",
+    "Place": "as:Place",
+    "Profile": "as:Profile",
+    "Question": "as:Question",
+    "Reject": "as:Reject",
+    "Remove": "as:Remove",
+    "Service": "as:Service",
+    "TentativeAccept": "as:TentativeAccept",
+    "TentativeReject": "as:TentativeReject",
+    "Tombstone": "as:Tombstone",
+    "Undo": "as:Undo",
+    "Update": "as:Update",
+    "Video": "as:Video",
+    "View": "as:View",
+    "Listen": "as:Listen",
+    "Read": "as:Read",
+    "Move": "as:Move",
+    "Travel": "as:Travel",
+    "IsFollowing": "as:IsFollowing",
+    "IsFollowedBy": "as:IsFollowedBy",
+    "IsContact": "as:IsContact",
+    "IsMember": "as:IsMember",
+    "subject": {
+      "@id": "as:subject",
+      "@type": "@id"
+    },
+    "relationship": {
+      "@id": "as:relationship",
+      "@type": "@id"
+    },
+    "actor": {
+      "@id": "as:actor",
+      "@type": "@id"
+    },
+    "attributedTo": {
+      "@id": "as:attributedTo",
+      "@type": "@id"
+    },
+    "attachment": {
+      "@id": "as:attachment",
+      "@type": "@id"
+    },
+    "bcc": {
+      "@id": "as:bcc",
+      "@type": "@id"
+    },
+    "bto": {
+      "@id": "as:bto",
+      "@type": "@id"
+    },
+    "cc": {
+      "@id": "as:cc",
+      "@type": "@id"
+    },
+    "context": {
+      "@id": "as:context",
+      "@type": "@id"
+    },
+    "current": {
+      "@id": "as:current",
+      "@type": "@id"
+    },
+    "first": {
+      "@id": "as:first",
+      "@type": "@id"
+    },
+    "generator": {
+      "@id": "as:generator",
+      "@type": "@id"
+    },
+    "icon": {
+      "@id": "as:icon",
+      "@type": "@id"
+    },
+    "image": {
+      "@id": "as:image",
+      "@type": "@id"
+    },
+    "inReplyTo": {
+      "@id": "as:inReplyTo",
+      "@type": "@id"
+    },
+    "items": {
+      "@id": "as:items",
+      "@type": "@id"
+    },
+    "instrument": {
+      "@id": "as:instrument",
+      "@type": "@id"
+    },
+    "orderedItems": {
+      "@id": "as:items",
+      "@type": "@id",
+      "@container": "@list"
+    },
+    "last": {
+      "@id": "as:last",
+      "@type": "@id"
+    },
+    "location": {
+      "@id": "as:location",
+      "@type": "@id"
+    },
+    "next": {
+      "@id": "as:next",
+      "@type": "@id"
+    },
+    "object": {
+      "@id": "as:object",
+      "@type": "@id"
+    },
+    "oneOf": {
+      "@id": "as:oneOf",
+      "@type": "@id"
+    },
+    "anyOf": {
+      "@id": "as:anyOf",
+      "@type": "@id"
+    },
+    "closed": {
+      "@id": "as:closed",
+      "@type": "xsd:dateTime"
+    },
+    "origin": {
+      "@id": "as:origin",
+      "@type": "@id"
+    },
+    "accuracy": {
+      "@id": "as:accuracy",
+      "@type": "xsd:float"
+    },
+    "prev": {
+      "@id": "as:prev",
+      "@type": "@id"
+    },
+    "preview": {
+      "@id": "as:preview",
+      "@type": "@id"
+    },
+    "replies": {
+      "@id": "as:replies",
+      "@type": "@id"
+    },
+    "result": {
+      "@id": "as:result",
+      "@type": "@id"
+    },
+    "audience": {
+      "@id": "as:audience",
+      "@type": "@id"
+    },
+    "partOf": {
+      "@id": "as:partOf",
+      "@type": "@id"
+    },
+    "tag": {
+      "@id": "as:tag",
+      "@type": "@id"
+    },
+    "target": {
+      "@id": "as:target",
+      "@type": "@id"
+    },
+    "to": {
+      "@id": "as:to",
+      "@type": "@id"
+    },
+    "url": {
+      "@id": "as:url",
+      "@type": "@id"
+    },
+    "altitude": {
+      "@id": "as:altitude",
+      "@type": "xsd:float"
+    },
+    "content": "as:content",
+    "contentMap": {
+      "@id": "as:content",
+      "@container": "@language"
+    },
+    "name": "as:name",
+    "nameMap": {
+      "@id": "as:name",
+      "@container": "@language"
+    },
+    "duration": {
+      "@id": "as:duration",
+      "@type": "xsd:duration"
+    },
+    "endTime": {
+      "@id": "as:endTime",
+      "@type": "xsd:dateTime"
+    },
+    "height": {
+      "@id": "as:height",
+      "@type": "xsd:nonNegativeInteger"
+    },
+    "href": {
+      "@id": "as:href",
+      "@type": "@id"
+    },
+    "hreflang": "as:hreflang",
+    "latitude": {
+      "@id": "as:latitude",
+      "@type": "xsd:float"
+    },
+    "longitude": {
+      "@id": "as:longitude",
+      "@type": "xsd:float"
+    },
+    "mediaType": "as:mediaType",
+    "published": {
+      "@id": "as:published",
+      "@type": "xsd:dateTime"
+    },
+    "radius": {
+      "@id": "as:radius",
+      "@type": "xsd:float"
+    },
+    "rel": "as:rel",
+    "startIndex": {
+      "@id": "as:startIndex",
+      "@type": "xsd:nonNegativeInteger"
+    },
+    "startTime": {
+      "@id": "as:startTime",
+      "@type": "xsd:dateTime"
+    },
+    "summary": "as:summary",
+    "summaryMap": {
+      "@id": "as:summary",
+      "@container": "@language"
+    },
+    "totalItems": {
+      "@id": "as:totalItems",
+      "@type": "xsd:nonNegativeInteger"
+    },
+    "units": "as:units",
+    "updated": {
+      "@id": "as:updated",
+      "@type": "xsd:dateTime"
+    },
+    "width": {
+      "@id": "as:width",
+      "@type": "xsd:nonNegativeInteger"
+    },
+    "describes": {
+      "@id": "as:describes",
+      "@type": "@id"
+    },
+    "formerType": {
+      "@id": "as:formerType",
+      "@type": "@id"
+    },
+    "deleted": {
+      "@id": "as:deleted",
+      "@type": "xsd:dateTime"
+    },
+    "inbox": {
+      "@id": "ldp:inbox",
+      "@type": "@id"
+    },
+    "outbox": {
+      "@id": "as:outbox",
+      "@type": "@id"
+    },
+    "following": {
+      "@id": "as:following",
+      "@type": "@id"
+    },
+    "followers": {
+      "@id": "as:followers",
+      "@type": "@id"
+    },
+    "streams": {
+      "@id": "as:streams",
+      "@type": "@id"
+    },
+    "preferredUsername": "as:preferredUsername",
+    "endpoints": {
+      "@id": "as:endpoints",
+      "@type": "@id"
+    },
+    "uploadMedia": {
+      "@id": "as:uploadMedia",
+      "@type": "@id"
+    },
+    "proxyUrl": {
+      "@id": "as:proxyUrl",
+      "@type": "@id"
+    },
+    "liked": {
+      "@id": "as:liked",
+      "@type": "@id"
+    },
+    "oauthAuthorizationEndpoint": {
+      "@id": "as:oauthAuthorizationEndpoint",
+      "@type": "@id"
+    },
+    "oauthTokenEndpoint": {
+      "@id": "as:oauthTokenEndpoint",
+      "@type": "@id"
+    },
+    "provideClientKey": {
+      "@id": "as:provideClientKey",
+      "@type": "@id"
+    },
+    "signClientKey": {
+      "@id": "as:signClientKey",
+      "@type": "@id"
+    },
+    "sharedInbox": {
+      "@id": "as:sharedInbox",
+      "@type": "@id"
+    },
+    "Public": {
+      "@id": "as:Public",
+      "@type": "@id"
+    },
+    "source": "as:source",
+    "likes": {
+      "@id": "as:likes",
+      "@type": "@id"
+    },
+    "shares": {
+      "@id": "as:shares",
+      "@type": "@id"
+    }
+  }
+}
diff --git a/spec/fixtures/requests/json-ld.identity.txt b/spec/fixtures/requests/json-ld.identity.txt
new file mode 100644
index 000000000..8810526cb
--- /dev/null
+++ b/spec/fixtures/requests/json-ld.identity.txt
@@ -0,0 +1,100 @@
+HTTP/1.1 200 OK

+Accept-Ranges: bytes

+Access-Control-Allow-Headers: DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding

+Access-Control-Allow-Origin: *

+Content-Type: application/ld+json

+Date: Tue, 01 May 2018 23:28:21 GMT

+Etag: "e26-547a6fc75b04a-gzip"

+Last-Modified: Fri, 03 Feb 2017 21:30:09 GMT

+Server: Apache/2.4.7 (Ubuntu)

+Vary: Accept-Encoding

+Transfer-Encoding: chunked

+

+{
+  "@context": {
+    "id": "@id",
+    "type": "@type",
+
+    "cred": "https://w3id.org/credentials#",
+    "dc": "http://purl.org/dc/terms/",
+    "identity": "https://w3id.org/identity#",
+    "perm": "https://w3id.org/permissions#",
+    "ps": "https://w3id.org/payswarm#",
+    "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
+    "rdfs": "http://www.w3.org/2000/01/rdf-schema#",
+    "sec": "https://w3id.org/security#",
+    "schema": "http://schema.org/",
+    "xsd": "http://www.w3.org/2001/XMLSchema#",
+
+    "Group": "https://www.w3.org/ns/activitystreams#Group",
+
+    "claim": {"@id": "cred:claim", "@type": "@id"},
+    "credential": {"@id": "cred:credential", "@type": "@id"},
+    "issued": {"@id": "cred:issued", "@type": "xsd:dateTime"},
+    "issuer": {"@id": "cred:issuer", "@type": "@id"},
+    "recipient": {"@id": "cred:recipient", "@type": "@id"},
+    "Credential": "cred:Credential",
+    "CryptographicKeyCredential": "cred:CryptographicKeyCredential",
+
+    "about": {"@id": "schema:about", "@type": "@id"},
+    "address": {"@id": "schema:address", "@type": "@id"},
+    "addressCountry": "schema:addressCountry",
+    "addressLocality": "schema:addressLocality",
+    "addressRegion": "schema:addressRegion",
+    "comment": "rdfs:comment",
+    "created": {"@id": "dc:created", "@type": "xsd:dateTime"},
+    "creator": {"@id": "dc:creator", "@type": "@id"},
+    "description": "schema:description",
+    "email": "schema:email",
+    "familyName": "schema:familyName",
+    "givenName": "schema:givenName",
+    "image": {"@id": "schema:image", "@type": "@id"},
+    "label": "rdfs:label",
+    "name": "schema:name",
+    "postalCode": "schema:postalCode",
+    "streetAddress": "schema:streetAddress",
+    "title": "dc:title",
+    "url": {"@id": "schema:url", "@type": "@id"},
+    "Person": "schema:Person",
+    "PostalAddress": "schema:PostalAddress",
+    "Organization": "schema:Organization",
+
+    "identityService": {"@id": "identity:identityService", "@type": "@id"},
+    "idp": {"@id": "identity:idp", "@type": "@id"},
+    "Identity": "identity:Identity",
+
+    "paymentProcessor": "ps:processor",
+    "preferences": {"@id": "ps:preferences", "@type": "@vocab"},
+
+    "cipherAlgorithm": "sec:cipherAlgorithm",
+    "cipherData": "sec:cipherData",
+    "cipherKey": "sec:cipherKey",
+    "digestAlgorithm": "sec:digestAlgorithm",
+    "digestValue": "sec:digestValue",
+    "domain": "sec:domain",
+    "expires": {"@id": "sec:expiration", "@type": "xsd:dateTime"},
+    "initializationVector": "sec:initializationVector",
+    "member": {"@id": "schema:member", "@type": "@id"},
+    "memberOf": {"@id": "schema:memberOf", "@type": "@id"},
+    "nonce": "sec:nonce",
+    "normalizationAlgorithm": "sec:normalizationAlgorithm",
+    "owner": {"@id": "sec:owner", "@type": "@id"},
+    "password": "sec:password",
+    "privateKey": {"@id": "sec:privateKey", "@type": "@id"},
+    "privateKeyPem": "sec:privateKeyPem",
+    "publicKey": {"@id": "sec:publicKey", "@type": "@id"},
+    "publicKeyPem": "sec:publicKeyPem",
+    "publicKeyService": {"@id": "sec:publicKeyService", "@type": "@id"},
+    "revoked": {"@id": "sec:revoked", "@type": "xsd:dateTime"},
+    "signature": "sec:signature",
+    "signatureAlgorithm": "sec:signatureAlgorithm",
+    "signatureValue": "sec:signatureValue",
+    "CryptographicKey": "sec:Key",
+    "EncryptedMessage": "sec:EncryptedMessage",
+    "GraphSignature2012": "sec:GraphSignature2012",
+    "LinkedDataSignature2015": "sec:LinkedDataSignature2015",
+
+    "accessControl": {"@id": "perm:accessControl", "@type": "@id"},
+    "writePermission": {"@id": "perm:writePermission", "@type": "@id"}
+  }
+}
diff --git a/spec/fixtures/requests/json-ld.security.txt b/spec/fixtures/requests/json-ld.security.txt
new file mode 100644
index 000000000..0d29903e6
--- /dev/null
+++ b/spec/fixtures/requests/json-ld.security.txt
@@ -0,0 +1,61 @@
+HTTP/1.1 200 OK

+Accept-Ranges: bytes

+Access-Control-Allow-Headers: DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding

+Access-Control-Allow-Origin: *

+Content-Type: application/ld+json

+Date: Wed, 02 May 2018 16:25:32 GMT

+Etag: "7e3-5651ec0f7c5ed-gzip"

+Last-Modified: Tue, 13 Feb 2018 21:34:04 GMT

+Server: Apache/2.4.7 (Ubuntu)

+Vary: Accept-Encoding

+Content-Length: 2019

+

+{
+  "@context": {
+    "id": "@id",
+    "type": "@type",
+
+    "dc": "http://purl.org/dc/terms/",
+    "sec": "https://w3id.org/security#",
+    "xsd": "http://www.w3.org/2001/XMLSchema#",
+
+    "EcdsaKoblitzSignature2016": "sec:EcdsaKoblitzSignature2016",
+    "Ed25519Signature2018": "sec:Ed25519Signature2018",
+    "EncryptedMessage": "sec:EncryptedMessage",
+    "GraphSignature2012": "sec:GraphSignature2012",
+    "LinkedDataSignature2015": "sec:LinkedDataSignature2015",
+    "LinkedDataSignature2016": "sec:LinkedDataSignature2016",
+    "CryptographicKey": "sec:Key",
+
+    "authenticationTag": "sec:authenticationTag",
+    "canonicalizationAlgorithm": "sec:canonicalizationAlgorithm",
+    "cipherAlgorithm": "sec:cipherAlgorithm",
+    "cipherData": "sec:cipherData",
+    "cipherKey": "sec:cipherKey",
+    "created": {"@id": "dc:created", "@type": "xsd:dateTime"},
+    "creator": {"@id": "dc:creator", "@type": "@id"},
+    "digestAlgorithm": "sec:digestAlgorithm",
+    "digestValue": "sec:digestValue",
+    "domain": "sec:domain",
+    "encryptionKey": "sec:encryptionKey",
+    "expiration": {"@id": "sec:expiration", "@type": "xsd:dateTime"},
+    "expires": {"@id": "sec:expiration", "@type": "xsd:dateTime"},
+    "initializationVector": "sec:initializationVector",
+    "iterationCount": "sec:iterationCount",
+    "nonce": "sec:nonce",
+    "normalizationAlgorithm": "sec:normalizationAlgorithm",
+    "owner": {"@id": "sec:owner", "@type": "@id"},
+    "password": "sec:password",
+    "privateKey": {"@id": "sec:privateKey", "@type": "@id"},
+    "privateKeyPem": "sec:privateKeyPem",
+    "publicKey": {"@id": "sec:publicKey", "@type": "@id"},
+    "publicKeyBase58": "sec:publicKeyBase58",
+    "publicKeyPem": "sec:publicKeyPem",
+    "publicKeyService": {"@id": "sec:publicKeyService", "@type": "@id"},
+    "revoked": {"@id": "sec:revoked", "@type": "xsd:dateTime"},
+    "salt": "sec:salt",
+    "signature": "sec:signature",
+    "signatureAlgorithm": "sec:signingAlgorithm",
+    "signatureValue": "sec:signatureValue"
+  }
+}